Image-guided radiation therapy produces lower acute and chronic gastrointestinal and genitourinary toxicity in prostate cancer patients
Abstract
Purpose: This paper compares individual radiation therapy techniques used for prostate cancer and their benefits in clinical practice. Methods: We retrospectively analyzed 921 patients with localized prostate tumors treated between 1997 and 2012.
We divided the patients into four groups according to the selected treatment technique (conformal radiation therapy [3DCRT], intensity-modulated radiation therapy [IMRT], image-guided radiation therapy [IGRT], and volumetricmodulated arc therapy [VMAT]) and evaluated the incidence of acute and chronic gastrointestinal (GI) and genitourinary (GU) toxicity. Results: The incidence of grade 2 or greater acute GU and GI toxicity was significantly higher among techniques other than IGRT (p<0.001).
We found the same results in the case of grade 3 or greater acute GU toxicity (p<0.001). Grade 3 or higher acute GI toxicity occurred only in one patient treated by 3DCRT.
Cumulative late GI toxicity of grade 2 or higher and grade 3 or higher was recorded over 3 years significantly more frequently among non-IGRT techniques as compared to IGRT (p<0.001). As regards GU toxicity, we found significantly higher incidence only for grade 2 or higher (p<0.001), not for grade 3 or higher.
No occurrence of grade 4 toxicity was recorded. The greatest incidence of patients without acute and chronic GI/GU toxicity was recorded in connection with VMAT.
Conclusions: IGRT demonstrated a pronounced reduction in acute and chronic GU and GI toxicity as compared to non-IGRT techniques in the treatment of localized prostate cancer.